The present invention is directed to sheets suitable as receiving substrates in printing and imaging processes. More specifically, the present invention is directed to recording sheets suitable for printing and imaging processes which contain layers of heat resistant polymers. One embodiment of the present invention is directed to a recording sheet which comprises, in the order stated, an ink receiving layer, a base sheet, a heat absorbing layer, and an anticurl layer.
Recording sheets suitable for various printing and imaging processes are known. For example, U.S. Pat. No. 4,528,242 (Burwasser), the disclosure of which is totally incorporated herein by reference, discloses an ink jet recording transparency capable of absorbing colored, aqueous-miscible inks to provide permanent smear-resistant images. The transparency includes a transparent resinous support and a coating which is clear and comprises a mixture of a carboxylated polymer or copolymer having a molecular weight of about 50,000 to 1 million, and a polyalkylene glycol having an average molecular weight of about 5,000 to 25,000, with the glycol being present in an amount of about 5 to about 70 percent of the polymer.
In addition, U.S. Pat. No. 4,547,405 (Bedell et al.), the disclosure of which is totally incorporated herein by reference, discloses an ink jet recording sheet comprising a transparent support carrying a layer comprising 5 to 100 percent by weight of a coalesced block copolymer latex of polyvinyl alcohol with polyvinyl (benzyl ammonium chloride) and 0 to 95 percent by weight of a water soluble polymer selected from the group consisting of polyvinyl alcohol, polyvinyl pyrrolidone, and copolymers thereof.
Further, U.S. Pat. No. 4,555,437 (Tanck), the disclosure of which is totally incorporated herein by reference, discloses a transparent recording medium which comprises a conventional transparency base material coated with hydroxyethylcellulose and optionally containing one or more additional polymers compatible therewith.
Additionally, U.S. Pat. No. 4,575,465 (Viola), the disclosure of which is totally incorporated herein by reference, discloses an ink jet recording sheet comprising a transparent support carrying a layer comprising up to 50 percent by weight of vinylpyridine/vinylbenzyl quaternary salt copolymer and a hydrophilic polymer selected from the group consisting of gelatin, polyvinyl alcohol, and hydroxypropyl cellulose and mixtures thereof.
U.S. Pat. No. 4,578,285 (Viola), the disclosure of which is totally incorporated herein by reference, discloses a printing substrate adapted to receive ink droplets to form an image generated by an ink jet printer which comprises a transparent support carrying a layer comprising at least 70 percent by weight polyurethane and 5 to 30 percent by weight of a polymer selected from the group consisting of polyvinylpyrrolidone, polyvinylpyrrolidone/vinyl acetate copolymer, poly(ethyleneoxide), gelatin, and polyaccylic acid.
In addition, U.S. Pat. No. 4,592,954 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a transparency for ink jet printing which comprises a supporting substrate and thereover a coating consisting essentially of a blend of carboxymethyl cellulose and polyethylene oxides. This patent also discloses papers for use in ink jet printing which comprise a plain paper substrate and a coating thereover consisting essentially of polyethylene oxides.
Further, U.S. Pat. No. 4,649,064 (Jones), the disclosure of which is totally incorporated herein by reference, discloses a rapid-drying image recording element adapted for water based liquid ink marking in devices such as pen plotters, ink printers and the like. The element comprises a support having thereon a hydrophilic ink receiving layer which is crosslinked to a degree sufficient to render it nonblocking and waterfast while permitting it to absorb rapidly a water-based liquid ink. The element is used in combination with a water-based liquid ink that comprises a water-dispersable crosslinkable colorant/resin composition and the ink receiving layer contains a crosslinking agent which crosslinks the colorant resin composition to render the markings smear resistant, abrasion resistant, and waterfast.
Additionally, U.S. Pat. No. 4,781,985 (Desjarlais), the disclosure of which is totally incorporated herein by reference, discloses an ink jet transparency which comprises a substantially transparent resinous support such as a polyester film and a substantially clear coating thereon which includes a specific fluorosurfactant.
U.S. Pat. No. 4,887,097 (Akiya et al.), the disclosure of which is totally incorporated herein by reference, discloses a recording medium having a substrate and an ink receiving layer provided on the substrate, wherein the ink receiving layer contains, in combination, solvent soluble resin (A) that is capable of absorbing water in an amount of 0.5 times or more as much as its own weight and is substantially water insoluble, and particles of solvent insoluble resin (B) that is capable of absorbing water in an amount of 50 times or more as much as its own weight.
In addition, U.S. Pat. No. 4,865,914 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a transparency which comprises a supporting substrate and a blend which comprises polyethylene oxide and carboxymethyl cellulose together with a component selected from the group consisting of (1) hydroxypropyl cellulose; (2) vinylmethyl ether/maleic acid copolymer; (3) carboxymethyl hydroxyethyl cellulose; (4) hydroxyethyl cellulose; (5) acrylamide/acrylic acid copolymer; (6) cellulose sulfate; (7) poly(2-acrylamido-2-methyl propane sulfonic acid); (8) poly(vinyl alcohol); (9) poly(vinyl pyrrolidone); and (10) hydroxypropyl methyl cellulose. Papers with these coatings are also disclosed.
Additional disclosures concerning recording sheets are disclosed in, for example, U.S. Pat. No. 3,535,112, U.S. Pat. No. 3,539,340, U.S. Pat. No. 4,071,362, U.S. Pat. No. 4,085,245, U.S. Pat. No. 4,259,422, U.S. Pat. No. 4,489,122, U.S. Pat. No. 4,526,847, U.S. Pat. No. 4,547,405, U.S. Pat. No. 4,575,465, U.S. Pat. No. 4,770,934, U.S. Pat. No. 4,865,914, U.S. Pat. No. 3,488,189, U.S. Pat. No. 3,493,412, U.S. Pat. No. 3,619,279, U.S. Pat. No. 3,539,341, U.S. Pat. No. 3,833,293, U.S. Pat. No. 3,854,942, U.S. Pat. No. 4,234,644, U.S. Pat. No. 4,419,004, U.S. Pat. No. 4,419,005, U.S. Pat. No. 4,480,003, U.S. Pat. No. 4,711,816, U.S. Pat. No. 4,637,974, U.S. Pat. No. 4,370,379, U.S. Pat. No. 4,599,293, U.S. Pat. No. 4,466,174, U.S. Pat. No. 4,371,582, U.S. Pat. No. 4,680,235, U.S. Pat. No. 4,775,594, U.S. Pat. No. 4,474,850, U.S. Pat. No. 4,592,954, U.S. Pat. No. 4,503,111, U.S. Pat. No. 4,650,714, U.S. Pat. No. 4,732,786, U.S. Pat. No. 4,308,542, U.S. Pat. No. 4,269,891, U.S. Pat. No. 4,371,582, U.S. Pat. No. 4,301,195, U.S. Pat. No. 4,578,285, U.S. Pat. No. 4,555,437, U.S. Pat. No. 4,711,816, U.S. Pat. No. 4,781,985, U.S. Pat. No. 4,686,118, U.S. Pat. No. 4,701,837, U.S. Pat. No. 3,320,089, U.S. Pat. No. 3,841,903, U.S. Pat. No. 4,770,934, and U.S. Pat. No. 4,830,911, the disclosures of each of which are totally incorporated herein by reference.
Heat resistant coating materials are also known. For example, U.S. Pat. No. 4,732,815 (Mizobuchi et al.) and U.S. Pat. No. 4,778,729 (Mizobuchi), the disclosures of each of which are totally incorporated herein by reference, disclose a heat transfer sheet comprising a base film and a hot melt ink layer formed on one surface of the base film, said hot melt ink layer comprising one or more components which impart filling to the printed areas of a transferable paper during transferring. Another type of heat transfer sheet comprising a base film, a hot melt ink layer laminated on one surface of the base film, and a filling layer laminated on the hot melt ink layer is also disclosed. The sheet can have a backing layer of a heat resistant antistick polymer such as silicone-modified acrylic resins, silicone-modified polyester resins, vinylidene fluoride resins, and the like.
In addition, U.S. Pat. No. 4,875,961 (Oike et al.), the disclosure of which is totally incorporated herein by reference, discloses a heat sensitive transfer medium comprising a support and a transfer layer comprising at least a nonflowable ink layer and an adhesive layer, said two layers being provided in that order from the support side. The transfer medium can have a backing layer of a material such as a fluorine containing polymer.
U.S. Pat. No. 5,068,140 (Malhotra et al.), the disclosure of which is totally incorporated herein by reference, discloses a transparency which comprises a hydrophilic coating and a plasticizer such as a phosphate, a substituted phthalic anhydride, a glycerol, a glycol, a substituted glycerol, a pyrrolidinone, an alkylene carbonate, a sulfolane, or a stearic acid derivative. Papers having the disclosed coatings are also included in the disclosure.
U.S. Pat. No. 5,068,140 (Malhotra et al.), the disclosure of which is totally incorporated herein by reference, discloses a transparent substrate material for receiving or containing an image which comprises a supporting substrate, an anticurl coating layer or coatings thereunder and an ink receiving layer thereover.
U.S. Pat. No. 4,956,225 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses transparencies suitable for electrographic and xerographic imaging which comprise a polymeric substrate with a toner receptive coating on one surface comprising blends of: poly(ethylene oxide) and carboxymethyl cellulose; poly(ethylene oxide), carboxymethyl cellulose and hydroxypropyl cellulose; poly(ethylene oxide) and vinylidene fluoride/hexafluoropropylene copolymer, poly(chloroprene) and poly(.alpha.-methylstyrene); poly(caprolactone) and poly(.alpha.-methylstyrene); poly(vinylisobutylether) and poly(.alpha.-methylstyrene); blends of poly(caprolactone) and poly(p-isopropyl .alpha.-methylstyrene); blends of poly(1,4-butylene adipate) and poly(.alpha.-methylstyrene); chlorinated poly(propylene) and poly(.alpha.-methylstyrene); chlorinated poly(ethylene) and poly(.alpha.-methylstyrene); and chlorinated rubber and poly(.alpha.-methylstyrene). This copending application also discloses transparencies suitable for electrographic and xerographic imaging processes comprising a supporting polymeric substrate with a toner receptive coating on one surface thereof which comprises: (a) a first layer coating of a crystalline polymer selected from the group consisting of poly(chloroprene), chlorinated rubbers, blends of poly(ethylene oxide), and vinylidene fluoride/hexafluoropropylene copolymers, chlorinated poly(propylene), chlorinated poly(ethylene), poly(vinylmethyl ketone), poly(caprolactone), poly(1,4-butylene adipate), poly(vinylmethyl ether), and poly(vinyl isobutylether); and (b) a second overcoating layer comprising a cellulose ether selected from the group consisting of hydroxypropyl methyl cellulose, hydroxypropyl cellulose and ethyl cellulose.
U.S. Pat. No. 4,997,697 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a transparent substrate material for receiving or containing an image which comprises a supporting substrate base, an antistatic polymer layer coated on one or both sides of the substrate and comprising hydrophilic cellulosic components, and a toner receiving polymer layer contained on one or both sides of the antistatic layer, which polymer comprises hydrophobic cellulose ethers, hydrophobic cellulose esters or mixtures thereof, and wherein the toner receiving layer contains adhesive components.
Copending application U.S. Ser. No. 07/370,677 (Malhotra), filed Jun. 23, 1989, the disclosure of which is totally incorporated herein by reference, discloses an imaged transparency comprising a supporting substrate, an oil absorbing layer which comprises, for example, chlorinated rubber, styrene-olefin copolymers, alkylmethacrylate copolymers, ethylene-propylene copolymers, sodium carboxymethyl cellulose or sodium carboxymethylhydroxyethyl cellulose, and ink receiving polymer layers comprising, for example, vinyl alcohol-vinyl acetate, vinyl alcohol-vinyl butyral or vinyl alcohol-vinyl acetate-vinyl chloride copolymers. The ink receiving layers may include therein or thereon fillers such as silica, calcium carbonate, or titanium dioxide.
U.S. Pat. No. 5,075,153 (Malhotra), the disclosure of which is totally incorporated herein by reference, discloses a never-tear coated paper comprising a plastic supporting substrate; a binder layer comprising polymers selected from the group consisting of (1) hydroxy propyl cellulose, (2) poly(vinyl alkyl ether), (3) vinyl pyrrolidone-vinyl acetate copolymer, (4) vinyl pyrrolidone-dialkylamino ethyl methacrylate copolymer quaternized, (5) poly(vinyl pyrrolidone), (6) poly(ethylene imine), and mixtures thereof; a pigment or pigments; and an ink receiving polymer layer.
Copending application U.S. Ser. No. 07/587,781 (Malhotra), filed Mar. 2, 1990, the disclosure of which is totally incorporated herein by reference, discloses all purpose xerographic transparencies with coatings thereover which are compatible with the toner compositions selected for development, and wherein the coatings enable images with acceptable optical densities. One disclosed transparency for ink jet printing processes and xerographic printing processes comprises a supporting substrate and a coating composition thereon which comprises a mixture selected from the classes of materials comprising (a) nonionic celluloses such as hydroxylpropylmethyl cellulose, hydroxyethyl cellulose, hydroxybutyl methyl cellulose, or mixtures thereof; (b) ionic celluloses such as anionic sodium carboxymethyl cellulose, anionic sodium carboxymethyl hydroxyethyl cellulose, cationic celluloses, or mixtures thereof; (c) poly(alkylene oxide) such as poly(ethylene oxide) together with a noncellulosic component selected from the group consisting of (1) poly(imidazoline) quaternized; (2) poly(N,N-dimethyl-3,5-dimethylene piperidinium chloride); (3) poly(2-acrylamido-2-methyl propane sulfonic acid); (4) poly(ethylene imine) epichlorohydrin; (5) poly(acrylamide); (6) acrylamide-acrylic acid copolymer; (7) poly(vinyl pyrrolidone); (8) poly(vinyl alcohol); (9) vinyl pyrrolidone-diethyl aminomethylmethacrylate copolymer quaternized; (10) vinyl pyrrolidonevinyl acetate copolymer; and mixtures thereof. The coating compositions are generally present on both sides of a supporting substrate, and in one embodiment the coating comprises nonionic hydroxyethyl cellulose, 25 percent by weight, anionic sodium carboxymethyl cellulose, 25 percent by weight, poly(ethylene oxide), 25 percent by weight, and poly(acrylamide), 25 percent by weight. The coating can also contain colloidal silica particles, a carbonate, such as calcium carbonate, and the like primarily for the purpose of transparency traction during the feeding process.
Copending application U.S. Ser. No. 07/544,577 (Malhotra), filed Jun. 27, 1990, the disclosure of which is totally incorporated herein by reference, discloses transparencies for electrophotographic processes, especially xerographic processes, ink jet printing processes, dot matrix printing processes and the like, comprising a supporting substrate and an ink or toner receiving coating composition on both sides of the substrate comprising an adhesive layer polymer such as chlorinated poly(isoprene), chlorinated poly(propylene), blends of phosphate esters with poly(styrene) and the like and an antistatic layer on both sides of the adhesive layer, which antistatic layer comprises complexes of metal halides such as potassium iodide, urea compounds such as urea phosphate with polymers containing oxyalkylene units such as poly(ethylene oxide), poly (propylene oxide), ethylene oxide/propylene oxide block copolymers, ethoxylated amines and the like, and an optional resin binder polymer such as poly(2-hydroxyethylmethacrylate), poly(2-hydroxypropylmethacrylate), hydroxypropylmethyl cellulose, or the like.
Although known recording sheets are suitable for their intended purposes, a need remains for recording sheets that do not exhibit curling and which retain their anticurl characteristics after exposure to heat. Known recording sheets, such as the transparency sheets disclosed in, for example, U.S. Pat. No. 4,592,954 and U.S. Pat. No. 4,865,914, generally comprise ink receiving coatings or layers on a base sheet. Frequently, the ink receiving layer is present on the base sheet in a coating weight of, for example, from about 8.0 to about 20.0 grams per square meter, and the layer frequently is present only on one side of the base sheet. These heavy coating weights can result in curling problems with the recording sheets, particularly when the sheets are transparencies used for projection of images. One possible method of avoiding the curling problem is to coat both surfaces of the base sheet with the ink receiving layer. Recording sheets bearing ink receiving layers on both surfaces, however, can present difficulties during stacking of the sheets, wherein an ink image is transferred from the printed surface of one recording sheet to the printed or nonprinted surface of another recording sheet. Another possible method of avoiding curling problems is to provide a recording sheet with a two-layered anticurl back layer, as disclosed in copending application U.S. Ser. No. 07/388,449. Recording sheets of this configuration perform well under all humidities at 80.degree. F. temperatures in printers that do not use heaters for fast drying of the ink images. When employed in printers equipped with heaters, however, these recording sheets may exhibit curling problems as a result of loss of moisture caused by the heating. Accordingly, there is a need for recording sheets that do not exhibit curl upon exposure to a wide range of relative humidities and do not curl subsequent to being subjected to heat.